We define a bicategory of topological defects \({B}_{\textsf {\tiny YM}}\)  in the spirit of [1]}, [2]}.
This bicategory has as objects regularised Frobenius algebras of the form \(A=L^2(G)\)  where \(G\)  is a
compact semi-simple Lie group. The 1-morphisms \(X:A\longrightarrow B\)  are transmissive bimodules with duals
and the composition is given by the relative tensor product.
The 2-morphisms \(X\Longrightarrow Y\)  for \(X,Y:A\longrightarrow B\)  are given by the set of families
of maps \(\lbrace \phi _{a}:\mathbb {C}\longrightarrow \  \circlearrowleft _A Y\otimes _B \bar{X}\rbrace _{a\in \mathbb {R}_{>0}}\) 
which are invariant under the action of cylinders:This
definition is an incarnation of the operator-state correspondence of
local quantum field theory.
\(\mathcal {C}_b \circ \phi _{a}=\phi _{a+b} \ ,\) 
